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101.
[目的]考虑环境和耕地约束,构建了城镇化效率测算指标体系,测算并分析我国2000~2014年区域城镇化效率,并且从城镇化发展模式与产业结构分布形态2个角度探索区域城镇化效率差异的机理。[方法]以"工业三废"和耕地面积减少量作为非合意产出,构建了由11个指标组成的投入—合意产出—非合意产出指标体系,进而利用优化ISBM模型测算了2000~2014年我国区域城镇化效率,并利用谱系聚类方法分析了其梯队层次特征。[结果]我国各省域城镇化效率总体较低,绝大多数省域处于效率缺损的状态;各省域城镇化效率表现为明显的5个梯队层次,不同区域、不同梯队省域城镇化效率存在明显差异,总体呈现出东、中、西依次递减的格局,并且省域之间城镇化效率差距自2000年以来呈不断缩小的趋势;东部地区城镇化效率较高,总体上城镇化与产业结构之间相互协调,城市群发展程度高而使得城市之间的分工合作程度高;中西部地区城镇化效率相对较低,产业结构对经济的支撑作用相对较弱,城市体系断层明显,城市群带动作用弱。[结论]我国区域城镇化效率总体较低且不平衡,这在很大程度上取决于城镇化模式和演进机制,区域之间的城镇化效率差异体现在产业结构层次、城市集聚方式以及劳动力转移方式等方面。  相似文献   
102.
公共政策研拟,尤其是环境影响评估,不仅牵涉技术性科学层面,同时涵盖社会性价值评估与政策性决策判断。旨在探讨如何将科学、价值与判断等因素合理融合于环境影响评估作业过程中,并据此研拟一环境影响评估架构,作为中国台湾地区环保部门开发案审核依据之参考。本文所研拟之环境影响评估架构的理论基础包括社会选择理论、社会判断理论及多属性评估方法。通过社会选择理论分析环境政策制定的机制;通过社会判断理论解释科学与价值如何整合于政策制定及其可行性中;而通过多属性评估方法建立开发案评选的集体决策技术。以山坡地开发为例说明此架构在实践中的应用。  相似文献   
103.
Background: Biologic treatments have enhanced the treatment outcomes of patients with active ankylosing spondylitis (AS). Until recently, TNF-alpha-inhibitors have been the only biologics approved for the treatment of active AS. The objective of this study was to assess the potential financial impact of the first non-TNF-alpha biologic secukinumab (fully human IL-17A-inhibitor) vs adalimumab (TNF-alpha-inhibitor) in the treatment of AS in Finland.

Materials and methods: In this model-based budget impact analysis, patients were treated either with secukinumab (150?mg) or adalimumab (40?mg). The number of patients and market share of different biologics were based on national reimbursement registry data. Adalimumab was the most commonly used biologic treatment for AS, and in the base case analysis all adalimumab patients are assumed to switch to secukinumab. Response rates were based on a matching-adjusted indirect comparison between secukinumab and adalimumab. Patients not achieving response were switched to another biologic treatment.

Results: Treating AS patients with secukinumab instead of adalimumab leads to potential savings of 18.2 million euros within a 5-year time period. The total costs within the follow-up time were 59.5 million euros and 77.7 million euros with and without secukinumab, respectively. According to sensitivity analyses, a higher adoption rate of secukinumab corresponds to higher potential savings.

Conclusions: Secukinumab is a cost-saving treatment option compared with adalimumab in the treatment of AS in Finland. More patients could be treated with a biologic by allocating resources more efficiently.  相似文献   
104.
Aims: This study aimed to evaluate the budget impact of niraparib and olaparib in patients with platinum-sensitive, recurrent ovarian cancer from a US third party payer perspective.

Materials and methods: A budget impact model was constructed to assess the additional per member per month (PMPM) costs associated with the introduction of niraparib and olaparib, two poly ADP-ribose polymerase ribose polymerase (PARP) inhibitors recently approved to be used in platinum-sensitive, recurrent ovarian cancer patients with and without a gBRCA mutation. The model assessed both pharmacy costs and medical costs. Pharmacy costs included adjusted drug costs, coinsurance, and dispensing fees. Medical costs included costs associated with disease monitoring and management of adverse events from the treatment. Epidemiological data from the literature were used to estimate the target population size. The analysis used 1-year time frame, and patients were assumed on treatment until disease progression or death. All costs were computed in 2017 USD. One-way sensitivity analyses were conducted to evaluate the model robustness.

Results: In a hypothetical plan of 1,000,000 members, 206 patients were estimated to be potential candidates for niraparib or olaparib maintenance treatment after applying all epidemiological parameters. At listed 30-day supply WAC prices of $14,750 for niraparib and $13,482 for olaparib, budget impacts of these two drugs were $0.169 PMPM and $0.156 PMPM, respectively, most of which were contributed by pharmacy costs. Sensitivity analyses suggested that assumptions around market share, platinum-sensitive rate after first treatment, and WAC prices affected results the most.

Limitations: In this model, it was assumed that adopting niraparib and olaparib would not affect utilization of existing medications. Also, the estimated clinical parameters from clinical trials could differ from real-world data.  相似文献   

105.
In this editorial, we reflect on how the Journal of Sustainable Tourism can contribute towards sustainable tourism researchers achieving more impact with their research. We propose some changes that can be tested in, and introduced gradually and collaboratively with, the community of the editorial board and authors. To support impactful mind sets, we will promote research that reflects diverse academic communities. To promote impactful research topics, we will encourage authors to frame their submitted articles against the Sustainable Development Goals, while research that is time sensitive will be fast tracked so it can contribute to current debates. To promote impactful methodologies, we shall favour articles that use mixed methods and action research, and those that conduct longitudinal, experimental, and evaluative research. To promote impactful partnerships, we will favour multidisciplinary approaches and research that has been co-created with stakeholders. To promote impactful communication and dissemination, we will continue to build an online community on social media for sustainable tourism researchers, we will promote articles in social media to raise their visibility, and we will provide free access to those articles that are deemed to have the greatest potential to impact positively on society.  相似文献   
106.
《Business Horizons》2019,62(3):373-382
The labor market has long included individuals seeking nonemployee, alternative work arrangements. Now, alternative work arrangements such as freelancing, independent contracting, and temporary contracts have entered the lexicon through the following terminology: the gig economy, the sharing economy, the YouEconomy, agile workforce, and contingent workers. There are currently an estimated 18.6 million independent contractors engaged in direct selling. This article reports the first attempt to empirically investigate and document both the economic and social impacts of direct selling in the U.S. Our findings suggest that direct selling has a consequential impact on the U.S. economy and that the direct selling experience fosters a variety of skills that benefit professional activities as well as the personal lives of millions of independent workers.  相似文献   
107.
Voluntary pricing mechanisms, such as Pay-What-You-Want (PWYW), could be a better pricing strategy to substitute for cash discount promotions. They can effectively promote the sales of conventional goods and services, while being influenced by socio-psychological variables. However, there is no clarity on the relative assessment of the impact of pricing frames, such as PWYW and Mark-Off-Your-Own-Price (MOYOP), on the consumers’ purchase of green products, where the purchase consideration might vary as the environment protection (altruistic) consideration versus the self-interest (self-enhancing) consideration. Further, there remains ambiguity on when and why such pricing mechanisms will work. This study, through an experiment, examines the buyers’ varied responses for the PWYW price frame versus the MOYOP price frame versus the fixed price frame under the environment protection (altruistic) consideration versus the self-interest (self-enhancing) consideration. It shows that although buyers do not show any difference in the mean voluntary payment between PWYW versus MOYOP frames as such; they prefer PWYW price frame under the environment protection (altruistic) consideration and MOYOP price frame under the self-interest (self-enhancing) consideration. The results show that the perception of price fairness mediates the relationship between pricing mechanism and willingness to buy (WTB). Furthermore, this study finds that price consciousness impacts the indirect effect of pricing mechanisms on WTB via perceived price fairness. The present study is the first to examine and analyze different considerations when the buyers’ preference varied for the PWYW versus MOYOP pricing frames. This study has suggested the underlying role of the perception of price fairness and price consciousness in the participative pricing mechanism on purchase.  相似文献   
108.
在复杂电磁环境下,由于民航地空通信大频偏的要求,滤波器无法滤除波道内的干扰。针对此问题,提出了一种自适应抗干扰系统设计方法。对于落在波道内且与地空通信信号有效频带不重叠的干扰,首先对通信信号进行载波频率估计,然后使用自适应滤波方法进行干扰抑制;对于落在波道内且与地空通信信号有效频带重叠的恒包络干扰,首先重构载波信号,消除对恒包络信号估计的影响,然后根据恒包络信号的特性重构干扰信号并进行干扰分离。实验结果表明,该系统设计方法在不改变民航地空通信架构的前提下,抗有效频带外干扰的能力最大可以提升23.8 dB,抗恒包络干扰的能力最大可以提升39.4 dB,从而可以大幅提高航空飞行安全水平。  相似文献   
109.
We extend some results of the Itô calculus to functionals of the current path of a process to reflect the fact that often the impact of randomness is cumulative and depends on the history of the process, not merely on its current value. We express the differential of the functional in terms of adequately defined partial derivatives to obtain an Itô formula. We develop an extension of the Feynman-Kac formula to the functional case and an explicit expression of the integrand in the Martingale Representation Theorem. We establish that under certain conditions, even path dependent options prices satisfy a partial differential equation in a local sense. We exploit this fact to find an expression of the price difference between two models and compute variational derivatives with respect to the volatility surface.  相似文献   
110.
Social Impact Bonds (SIBs) have emerged in recent years as outcome‐based public‐private partnerships (PPP) for the delivery of welfare services, where the payment to the private operator is linked to the achievement of superior social impact. Since the traditional infrastructure‐based PPP approach seems to have failed to achieve higher level of efficiency and, above all, effectiveness, this paper discusses the extent to which the SIB model can represent a reference point to innovate the PPP model by introducing more focus on outcome achievement and social value generation.  相似文献   
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